2 datasets found

The Global Lakes and Wetlands Database (GLWD) version 2 provides a comprehensive and seamless global map of inland surface waters distinguished into 33 waterbody and wetland types. GLWD v2 was developed by harmonizing the best available ground- and satellite-based data sources and has been designed to represent the maximum non-overlapping extents of aquatic ecosystems over the broad contemporary period of 1990-2020.

GLWD v2 represents a total of 18.2 million km2 of wetlands at a grid cell resolution of 15 arc-seconds (approximately 500 m at the equator). The data consist of a map of the dominant waterbody or wetland type in each grid cell, as well as 33 individual class layers which represent the sub-cell fraction of each specific class within each grid cell.

Version 2 of GLWD (Lehner et al., 2025) is the successor of the widely-used GLWD version 1 (Lehner & Döll, 2004). The quality, resolution, and format of GLWD v2 significantly improves upon GLWD v1 and supersedes the older version.

Large-sample datasets are essential in hydrological science to support modelling studies and global assessments. The present dataset compiles all freshwater quality data that is available under open data policy (CC BY 4.0 or equivalent) at the GEMStat database for global water quality (www.gemstat.org). It includes over 20,000,000 measurements on 608 water quality parameters, covering 13,660 stations in 37 countries over the time period from 1906 to 2023.

GEMStat is operated by the GEMS/Water programme of the United Nations Environment Programme (UNEP) and hosted at the International Centre for Water Resources and Global Change (ICWRGC) and the German Federal Institute of Hydrology (BfG). The data in GEMStat is provided by National Hydrological Services of UN member states.